Fix phantom state of opted-out files made non-optional

Now always asks the user before proceeding past the point where optional mods could be selected and configured
When updating files, the hash is checked so an update isn't redownloaded if it already exists
Added DevMain file for running in a dev environment

build.gradle.kts

@@ -1,9 +1,9 @@
 buildscript {
 	repositories {
-		jcenter()
+		mavenCentral()
 	}
 	dependencies {
-		classpath("com.guardsquare:proguard-gradle:7.0.0") {
+		classpath("com.guardsquare:proguard-gradle:7.1.0") {
 			exclude("com.android.tools.build")
 		}
 	}
@@ -12,30 +12,30 @@ buildscript {
 plugins {
 	java
 	application
-	id("com.github.johnrengelman.shadow") version "6.1.0"
-	id("com.palantir.git-version") version "0.12.3"
+	id("com.github.johnrengelman.shadow") version "7.1.2"
+	id("com.palantir.git-version") version "0.13.0"
 	id("com.github.breadmoirai.github-release") version "2.2.12"
-	kotlin("jvm") version "1.4.21"
-	id("com.github.jk1.dependency-license-report") version "1.16"
+	kotlin("jvm") version "1.6.10"
+	id("com.github.jk1.dependency-license-report") version "2.0"
+	`maven-publish`
 }
 
 java {
 	sourceCompatibility = JavaVersion.VERSION_1_8
 }
 
-val shrinkClasspath: Configuration by configurations.creating
-
-dependencies {
-	implementation("commons-cli:commons-cli:1.4")
-	shrinkClasspath("commons-cli:commons-cli:1.4")
-	implementation("com.moandjiezana.toml:toml4j:0.7.2")
-	implementation("com.google.code.gson:gson:2.8.1")
-	implementation("com.squareup.okio:okio:2.9.0")
-	implementation(kotlin("stdlib-jdk8"))
+repositories {
+	mavenCentral()
 }
 
-repositories {
-	jcenter()
+dependencies {
+	implementation("commons-cli:commons-cli:1.5.0")
+	implementation("com.moandjiezana.toml:toml4j:0.7.2")
+	implementation("com.google.code.gson:gson:2.8.9")
+	implementation("com.squareup.okio:okio:3.0.0")
+	implementation(kotlin("stdlib-jdk8"))
+	implementation("com.squareup.okhttp3:okhttp:4.9.3")
+	implementation("com.michael-bull.kotlin-result:kotlin-result:1.1.14")
 }
 
 application {
@@ -59,41 +59,47 @@ licenseReport {
 	filters = arrayOf<com.github.jk1.license.filter.DependencyFilter>(com.github.jk1.license.filter.LicenseBundleNormalizer())
 }
 
-// TODO: build relocated jar for minecraft launcher lib, non-relocated jar for packwiz-installer
-//tasks.register<com.github.jengelman.gradle.plugins.shadow.tasks.ConfigureShadowRelocation>("relocateShadowJar") {
-//	target = tasks.shadowJar.get()
-//	prefix = "link.infra.packwiz.deps"
-//}
-
-// Commons CLI and Minimal JSON are already included in packwiz-installer-bootstrap
 tasks.shadowJar {
-	dependencies {
-		exclude(dependency("commons-cli:commons-cli:1.4"))
-		exclude(dependency("com.eclipsesource.minimal-json:minimal-json:0.9.5"))
-		// TODO: exclude meta inf files
-	}
 	exclude("**/*.kotlin_metadata")
 	exclude("**/*.kotlin_builtins")
 	exclude("META-INF/maven/**/*")
 	exclude("META-INF/proguard/**/*")
-	//dependsOn(tasks.named("relocateShadowJar"))
+
+	// Relocate Commons CLI, so that it doesn't clash with old packwiz-installer-bootstrap (that shades it)
+	relocate("org.apache.commons.cli", "link.infra.packwiz.installer.deps.commons-cli")
+
+	// from Commons CLI
+	exclude("META-INF/LICENSE.txt")
+	exclude("META-INF/NOTICE.txt")
 }
 
 tasks.register<proguard.gradle.ProGuardTask>("shrinkJar") {
 	injars(tasks.shadowJar)
-	libraryjars(files(shrinkClasspath.files))
 	outjars("build/libs/" + tasks.shadowJar.get().outputs.files.first().name.removeSuffix(".jar") + "-shrink.jar")
 	if (System.getProperty("java.version").startsWith("1.")) {
 		libraryjars("${System.getProperty("java.home")}/lib/rt.jar")
 		libraryjars("${System.getProperty("java.home")}/lib/jce.jar")
 	} else {
-		throw RuntimeException("Compiling with Java 9+ not supported!")
+		// Use jmods for Java 9+
+		val mods = listOf("java.base", "java.logging", "java.desktop", "java.sql")
+		for (mod in mods) {
+			libraryjars(mapOf(
+				"jarfilter" to "!**.jar",
+				"filter" to "!module-info.class"
+			), "${System.getProperty("java.home")}/jmods/$mod.jmod")
+		}
 	}
 
 	keep("class link.infra.packwiz.installer.** { *; }")
 	dontoptimize()
 	dontobfuscate()
+
+	// Used by Okio and OkHttp
 	dontwarn("org.codehaus.mojo.animal_sniffer.*")
+	dontwarn("okhttp3.internal.platform.**")
+	dontwarn("org.conscrypt.**")
+	dontwarn("org.bouncycastle.**")
+	dontwarn("org.openjsse.**")
 }
 
 // Used for vscode launch.json
@@ -126,12 +132,38 @@ if (project.hasProperty("github.token")) {
 tasks.compileKotlin {
 	kotlinOptions {
 		jvmTarget = "1.8"
-		freeCompilerArgs = listOf("-Xjvm-default=enable")
+		freeCompilerArgs = listOf("-Xjvm-default=enable", "-Xallow-result-return-type", "-Xopt-in=kotlin.io.path.ExperimentalPathApi")
 	}
 }
 tasks.compileTestKotlin {
 	kotlinOptions {
 		jvmTarget = "1.8"
-		freeCompilerArgs = listOf("-Xjvm-default=enable")
+		freeCompilerArgs = listOf("-Xjvm-default=enable", "-Xallow-result-return-type", "-Xopt-in=kotlin.io.path.ExperimentalPathApi")
 	}
 }
+
+if (project.hasProperty("bunnycdn.token")) {
+	publishing {
+		publications {
+			create<MavenPublication>("maven") {
+				groupId = "link.infra.packwiz"
+				artifactId = "packwiz-installer"
+
+				from(components["java"])
+			}
+		}
+		repositories {
+			maven {
+				url = uri("https://storage.bunnycdn.com/comp-maven")
+				credentials(HttpHeaderCredentials::class) {
+					name = "AccessKey"
+					value = findProperty("bunnycdn.token") as String?
+				}
+				authentication {
+					create<HttpHeaderAuthentication>("header")
+				}
+			}
+		}
+	}
+}
+

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.7.1-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.3.3-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

src/main/java/link/infra/packwiz/installer/RequiresBootstrap.java

@@ -8,8 +8,6 @@ public class RequiresBootstrap {
 	public static void main(String[] args) {
 		// Very small CLI implementation, because Commons CLI complains on unexpected
 		// options
-		// Also so that Commons CLI can be excluded from the shaded JAR, as it is
-		// included in the bootstrap
 		if (Arrays.stream(args).map(str -> {
 			if (str == null) return "";
 			if (str.startsWith("--")) {

src/main/kotlin/link/infra/packwiz/installer/DevMain.kt

@@ -0,0 +1,5 @@
+package link.infra.packwiz.installer
+
+fun main(args: Array<String>) {
+	Main(args)
+}

src/main/kotlin/link/infra/packwiz/installer/DownloadTask.kt

@@ -6,19 +6,20 @@ import link.infra.packwiz.installer.metadata.SpaceSafeURI
 import link.infra.packwiz.installer.metadata.hash.Hash
 import link.infra.packwiz.installer.metadata.hash.HashUtils.getHash
 import link.infra.packwiz.installer.metadata.hash.HashUtils.getHasher
+import link.infra.packwiz.installer.target.Side
 import link.infra.packwiz.installer.ui.data.ExceptionDetails
 import link.infra.packwiz.installer.ui.data.IOptionDetails
 import link.infra.packwiz.installer.util.Log
-import okio.Buffer
-import okio.HashingSink
-import okio.buffer
+import okio.*
+import okio.Path.Companion.toOkioPath
 import java.io.IOException
 import java.nio.file.Files
 import java.nio.file.Paths
 import java.nio.file.StandardCopyOption
 import java.util.*
+import kotlin.io.use
 
-internal class DownloadTask private constructor(val metadata: IndexFile.File, defaultFormat: String, private val downloadSide: UpdateManager.Options.Side) : IOptionDetails {
+internal class DownloadTask private constructor(val metadata: IndexFile.File, defaultFormat: String, private val downloadSide: Side) : IOptionDetails {
 	var cachedFile: ManifestFile.File? = null
 
 	private var err: Exception? = null
@@ -26,7 +27,7 @@ internal class DownloadTask private constructor(val metadata: IndexFile.File, de
 
 	fun failed() = err != null
 
-	private var alreadyUpToDate = false
+	var alreadyUpToDate = false
 	private var metadataRequired = true
 	private var invalidated = false
 	// If file is new or isOptional changed to true, the option needs to be presented again
@@ -123,27 +124,77 @@ internal class DownloadTask private constructor(val metadata: IndexFile.File, de
 		}
 	}
 
+	/**
+	 * Check if the file in the destination location is already valid
+	 * Must be done after metadata retrieval
+	 */
+	fun validateExistingFile(packFolder: String) {
+		if (!alreadyUpToDate) {
+			try {
+				// TODO: only do this for files that didn't exist before or have been modified since last full update?
+				val destPath = Paths.get(packFolder, metadata.destURI.toString())
+				FileSystem.SYSTEM.source(destPath.toOkioPath()).buffer().use { src ->
+					val hash: Hash
+					val fileHashFormat: String
+					val linkedFile = metadata.linkedFile
+
+					if (linkedFile != null) {
+						hash = linkedFile.hash
+						fileHashFormat = linkedFile.download!!.hashFormat!!
+					} else {
+						hash = metadata.getHashObj()
+						fileHashFormat = metadata.hashFormat!!
+					}
+
+					val fileSource = getHasher(fileHashFormat).getHashingSource(src)
+					fileSource.buffer().readAll(blackholeSink())
+					if (fileSource.hashIsEqual(hash)) {
+						alreadyUpToDate = true
+
+						// Update the manifest file
+						cachedFile = (cachedFile ?: ManifestFile.File()).also {
+							try {
+								it.hash = metadata.getHashObj()
+							} catch (e: Exception) {
+								err = e
+								return
+							}
+							it.isOptional = isOptional
+							it.cachedLocation = metadata.destURI.toString()
+							metadata.linkedFile?.let { linked ->
+								try {
+									it.linkedFileHash = linked.hash
+								} catch (e: Exception) {
+									err = e
+								}
+							}
+						}
+					}
+				}
+			} catch (e: IOException) {
+				// Ignore exceptions; if the file doesn't exist we'll be downloading it
+			}
+		}
+	}
+
 	fun download(packFolder: String, indexUri: SpaceSafeURI) {
 		if (err != null) return
 
-		// TODO: is this necessary if we overwrite?
-		// Ensure it is removed
+		// Ensure wrong-side or optional false files are removed
 		cachedFile?.let {
-			if (!it.optionValue || !correctSide()) {
-				if (it.cachedLocation == null) return
-
-				try {
-					Files.deleteIfExists(Paths.get(packFolder, it.cachedLocation))
-				} catch (e: IOException) {
-					Log.warn("Failed to delete file before downloading", e)
+			if ((it.isOptional && !it.optionValue) || !correctSide()) {
+				if (it.cachedLocation != null) {
+					try {
+						Files.deleteIfExists(Paths.get(packFolder, it.cachedLocation))
+					} catch (e: IOException) {
+						Log.warn("Failed to delete file before downloading", e)
+					}
 				}
 				it.cachedLocation = null
 			}
 		}
 		if (alreadyUpToDate) return
 
-		// TODO: should I be validating JSON properly, or this fine!!!!!!!??
-		assert(metadata.destURI != null)
 		val destPath = Paths.get(packFolder, metadata.destURI.toString())
 
 		// Don't update files marked with preserve if they already exist on disk
@@ -163,10 +214,10 @@ internal class DownloadTask private constructor(val metadata: IndexFile.File, de
 
 			if (linkedFile != null) {
 				hash = linkedFile.hash
-				fileHashFormat = Objects.requireNonNull(Objects.requireNonNull(linkedFile.download)!!.hashFormat)!!
+				fileHashFormat = linkedFile.download!!.hashFormat!!
 			} else {
 				hash = metadata.getHashObj()
-				fileHashFormat = Objects.requireNonNull(metadata.hashFormat)!!
+				fileHashFormat = metadata.hashFormat!!
 			}
 
 			val src = metadata.getSource(indexUri)
@@ -183,7 +234,7 @@ internal class DownloadTask private constructor(val metadata: IndexFile.File, de
 				// isDirectory follows symlinks, but createDirectories doesn't
 				try {
 					Files.createDirectories(destPath.parent)
-				} catch (e: FileAlreadyExistsException) {
+				} catch (e: java.nio.file.FileAlreadyExistsException) {
 					if (!Files.isDirectory(destPath.parent)) {
 						throw e
 					}
@@ -196,7 +247,7 @@ internal class DownloadTask private constructor(val metadata: IndexFile.File, de
 				println("Calculated: " + fileSource.hash)
 				println("Expected:   $hash")
 				// Attempt to get the SHA256 hash
-				val sha256 = HashingSink.sha256(okio.blackholeSink())
+				val sha256 = HashingSink.sha256(blackholeSink())
 				data.readAll(sha256)
 				println("SHA256 hash value: " + sha256.hash)
 				err = Exception("Hash invalid!")
@@ -241,7 +292,7 @@ internal class DownloadTask private constructor(val metadata: IndexFile.File, de
 
 	companion object {
 		@JvmStatic
-		fun createTasksFromIndex(index: IndexFile, defaultFormat: String, downloadSide: UpdateManager.Options.Side): List<DownloadTask> {
+		fun createTasksFromIndex(index: IndexFile, defaultFormat: String, downloadSide: Side): List<DownloadTask> {
 			val tasks = ArrayList<DownloadTask>()
 			for (file in Objects.requireNonNull(index.files)) {
 				tasks.add(DownloadTask(file, defaultFormat, downloadSide))

src/main/kotlin/link/infra/packwiz/installer/Main.kt

@@ -3,6 +3,7 @@
 package link.infra.packwiz.installer
 
 import link.infra.packwiz.installer.metadata.SpaceSafeURI
+import link.infra.packwiz.installer.target.Side
 import link.infra.packwiz.installer.ui.cli.CLIHandler
 import link.infra.packwiz.installer.ui.gui.GUIHandler
 import link.infra.packwiz.installer.util.Log
@@ -68,7 +69,7 @@ class Main(args: Array<String>) {
 		val uOptions = try {
 			UpdateManager.Options.construct(
 				downloadURI = SpaceSafeURI(unparsedArgs[0]),
-				side = cmd.getOptionValue("side")?.let((UpdateManager.Options.Side)::from),
+				side = cmd.getOptionValue("side")?.let((Side)::from),
 				packFolder = cmd.getOptionValue("pack-folder"),
 				manifestFile = cmd.getOptionValue("meta-file")
 			)

src/main/kotlin/link/infra/packwiz/installer/UpdateManager.kt

@@ -3,33 +3,29 @@ package link.infra.packwiz.installer
 import com.google.gson.GsonBuilder
 import com.google.gson.JsonIOException
 import com.google.gson.JsonSyntaxException
-import com.google.gson.annotations.SerializedName
 import com.moandjiezana.toml.Toml
 import link.infra.packwiz.installer.DownloadTask.Companion.createTasksFromIndex
 import link.infra.packwiz.installer.metadata.IndexFile
 import link.infra.packwiz.installer.metadata.ManifestFile
 import link.infra.packwiz.installer.metadata.PackFile
 import link.infra.packwiz.installer.metadata.SpaceSafeURI
+import link.infra.packwiz.installer.metadata.curseforge.resolveCfMetadata
 import link.infra.packwiz.installer.metadata.hash.Hash
 import link.infra.packwiz.installer.metadata.hash.HashUtils.getHash
 import link.infra.packwiz.installer.metadata.hash.HashUtils.getHasher
 import link.infra.packwiz.installer.request.HandlerManager.getFileSource
 import link.infra.packwiz.installer.request.HandlerManager.getNewLoc
+import link.infra.packwiz.installer.target.Side
 import link.infra.packwiz.installer.ui.IUserInterface
 import link.infra.packwiz.installer.ui.IUserInterface.CancellationResult
 import link.infra.packwiz.installer.ui.IUserInterface.ExceptionListResult
 import link.infra.packwiz.installer.ui.data.InstallProgress
 import link.infra.packwiz.installer.util.Log
 import link.infra.packwiz.installer.util.ifletOrErr
-import link.infra.packwiz.installer.util.ifletOrWarn
 import okio.buffer
-import java.io.FileNotFoundException
-import java.io.FileReader
-import java.io.FileWriter
-import java.io.IOException
+import java.io.*
 import java.nio.file.Files
 import java.nio.file.Paths
-import java.util.*
 import java.util.concurrent.CompletionService
 import java.util.concurrent.ExecutionException
 import java.util.concurrent.ExecutorCompletionService
@@ -57,56 +53,6 @@ class UpdateManager internal constructor(private val opts: Options, val ui: IUse
 				Options(downloadURI, manifestFile ?: "packwiz.json", packFolder ?: ".", side ?: Side.CLIENT)
 		}
 
-		enum class Side {
-			@SerializedName("client")
-			CLIENT("client"),
-			@SerializedName("server")
-			SERVER("server"),
-			@SerializedName("both")
-			@Suppress("unused")
-			BOTH("both", arrayOf(CLIENT, SERVER));
-
-			private val sideName: String
-			private val depSides: Array<Side>?
-
-			constructor(sideName: String) {
-				this.sideName = sideName.toLowerCase()
-				depSides = null
-			}
-
-			constructor(sideName: String, depSides: Array<Side>) {
-				this.sideName = sideName.toLowerCase()
-				this.depSides = depSides
-			}
-
-			override fun toString() = sideName
-
-			fun hasSide(tSide: Side): Boolean {
-				if (this == tSide) {
-					return true
-				}
-				if (depSides != null) {
-					for (depSide in depSides) {
-						if (depSide == tSide) {
-							return true
-						}
-					}
-				}
-				return false
-			}
-
-			companion object {
-				fun from(name: String): Side? {
-					val lowerName = name.toLowerCase()
-					for (side in values()) {
-						if (side.sideName == lowerName) {
-							return side
-						}
-					}
-					return null
-				}
-			}
-		}
 	}
 
 	private fun start() {
@@ -140,7 +86,7 @@ class UpdateManager internal constructor(private val opts: Options, val ui: IUse
 		}
 		val pf = packFileSource.buffer().use {
 			try {
-				Toml().read(it.inputStream()).to(PackFile::class.java)
+				Toml().read(InputStreamReader(it.inputStream(), "UTF-8")).to(PackFile::class.java)
 			} catch (e: IllegalStateException) {
 				ui.showErrorAndExit("Failed to parse pack.toml", e)
 			}
@@ -180,8 +126,11 @@ class UpdateManager internal constructor(private val opts: Options, val ui: IUse
 		}
 
 		if (manifest.packFileHash?.let { packFileSource.hashIsEqual(it) } == true && invalidatedUris.isEmpty()) {
-			Log.info("Modpack is already up to date!")
 			// todo: --force?
+			ui.submitProgress(InstallProgress("Modpack is already up to date!", 1, 1))
+			if (manifest.cachedFiles.any { it.value.isOptional }) {
+				ui.awaitOptionalButton(false)
+			}
 			if (!ui.optionsButtonPressed) {
 				return
 			}
@@ -194,7 +143,8 @@ class UpdateManager internal constructor(private val opts: Options, val ui: IUse
 			handleCancellation()
 		}
 		try {
-			ifletOrWarn(pf.index, "No index file found") { index ->
+			// TODO: switch to OkHttp for better redirect handling
+			ui.ifletOrErr(pf.index, "No index file found, or the pack file is empty; note that Java doesn't automatically follow redirects from HTTP to HTTPS (and may cause this error)") { index ->
 				ui.ifletOrErr(index.hashFormat, index.hash, "Pack has no hash or hashFormat for index") { hashFormat, hash ->
 					ui.ifletOrErr(getNewLoc(opts.downloadURI, index.file), "Pack has invalid index file: " + index.file) { newLoc ->
 						processIndex(
@@ -237,10 +187,17 @@ class UpdateManager internal constructor(private val opts: Options, val ui: IUse
 
 	private fun processIndex(indexUri: SpaceSafeURI, indexHash: Hash, hashFormat: String, manifest: ManifestFile, invalidatedUris: List<SpaceSafeURI>) {
 		if (manifest.indexFileHash == indexHash && invalidatedUris.isEmpty()) {
-			Log.info("Modpack files are already up to date!")
+			ui.submitProgress(InstallProgress("Modpack files are already up to date!", 1, 1))
+			if (manifest.cachedFiles.any { it.value.isOptional }) {
+				ui.awaitOptionalButton(false)
+			}
 			if (!ui.optionsButtonPressed) {
 				return
 			}
+			if (ui.cancelButtonPressed) {
+				showCancellationDialog()
+				return
+			}
 		}
 		manifest.indexFileHash = indexHash
 
@@ -252,7 +209,7 @@ class UpdateManager internal constructor(private val opts: Options, val ui: IUse
 		}
 
 		val indexFile = try {
-			Toml().read(indexFileSource.buffer().inputStream()).to(IndexFile::class.java)
+			Toml().read(InputStreamReader(indexFileSource.buffer().inputStream(), "UTF-8")).to(IndexFile::class.java)
 		} catch (e: IllegalStateException) {
 			ui.showErrorAndExit("Failed to parse index file", e)
 		}
@@ -359,8 +316,20 @@ class UpdateManager internal constructor(private val opts: Options, val ui: IUse
 		// TODO: task failed function?
 		val nonFailedFirstTasks = tasks.filter { t -> !t.failed() }.toList()
 		val optionTasks = nonFailedFirstTasks.filter(DownloadTask::correctSide).filter(DownloadTask::isOptional).toList()
+		val optionsChanged = optionTasks.any(DownloadTask::isNewOptional)
+		if (optionTasks.isNotEmpty() && !optionsChanged) {
+			if (!ui.optionsButtonPressed) {
+				// TODO: this is so ugly
+				ui.submitProgress(InstallProgress("Reconfigure optional mods?", 0,1))
+				ui.awaitOptionalButton(true)
+				if (ui.cancelButtonPressed) {
+					showCancellationDialog()
+					return
+				}
+			}
+		}
 		// If options changed, present all options again
-		if (ui.optionsButtonPressed || optionTasks.any(DownloadTask::isNewOptional)) {
+		if (ui.optionsButtonPressed || optionsChanged) {
 			// new ArrayList is required so it's an IOptionDetails rather than a DownloadTask list
 			if (ui.showOptions(ArrayList(optionTasks))) {
 				cancelled = true
@@ -370,6 +339,38 @@ class UpdateManager internal constructor(private val opts: Options, val ui: IUse
 		// TODO: keep this enabled? then apply changes after download process?
 		ui.disableOptionsButton(optionTasks.isNotEmpty())
 
+		ui.submitProgress(InstallProgress("Validating existing files..."))
+
+		// Validate existing files
+		for (downloadTask in nonFailedFirstTasks.filter(DownloadTask::correctSide)) {
+			downloadTask.validateExistingFile(opts.packFolder)
+		}
+
+		// Resolve CurseForge metadata
+		val cfFiles = nonFailedFirstTasks.asSequence().filter { !it.alreadyUpToDate }
+			.filter(DownloadTask::correctSide)
+			.map { it.metadata }
+			.filter { it.linkedFile != null }
+			.filter { it.linkedFile?.download?.mode == "metadata:curseforge" }.toList()
+		if (cfFiles.isNotEmpty()) {
+			ui.submitProgress(InstallProgress("Resolving CurseForge metadata..."))
+			val resolveFailures = resolveCfMetadata(cfFiles)
+			if (resolveFailures.isNotEmpty()) {
+				errorsOccurred = true
+				when (ui.showExceptions(resolveFailures, cfFiles.size, true)) {
+					ExceptionListResult.CONTINUE -> {}
+					ExceptionListResult.CANCEL -> {
+						cancelled = true
+						return
+					}
+					ExceptionListResult.IGNORE -> {
+						cancelledStartGame = true
+						return
+					}
+				}
+			}
+		}
+
 		// TODO: different thread pool type?
 		val threadPool = Executors.newFixedThreadPool(10)
 		val completionService: CompletionService<DownloadTask> = ExecutorCompletionService(threadPool)
@@ -445,4 +446,5 @@ class UpdateManager internal constructor(private val opts: Options, val ui: IUse
 			exitProcess(0)
 		}
 	}
+
 }

src/main/kotlin/link/infra/packwiz/installer/metadata/IndexFile.kt

@@ -9,6 +9,7 @@ import link.infra.packwiz.installer.request.HandlerManager.getFileSource
 import link.infra.packwiz.installer.request.HandlerManager.getNewLoc
 import okio.Source
 import okio.buffer
+import java.io.InputStreamReader
 import java.nio.file.Paths
 
 class IndexFile {
@@ -43,7 +44,7 @@ class IndexFile {
 			linkedFileURI = getNewLoc(indexUri, file)
 			val src = getFileSource(linkedFileURI!!)
 			val fileStream = getHasher(hashFormat!!).getHashingSource(src)
-			linkedFile = Toml().read(fileStream.buffer().inputStream()).to(ModFile::class.java)
+			linkedFile = Toml().read(InputStreamReader(fileStream.buffer().inputStream(), "UTF-8")).to(ModFile::class.java)
 			if (!fileStream.hashIsEqual(fileHash)) {
 				throw Exception("Invalid mod file hash")
 			}
@@ -78,9 +79,9 @@ class IndexFile {
 			get() {
 				if (metafile) {
 					return linkedFile?.name ?: linkedFile?.filename ?:
-					file?.run { Paths.get(path).fileName.toString() } ?: "Invalid file"
+					file?.run { Paths.get(path ?: return "Invalid file").fileName.toString() } ?: "Invalid file"
 				}
-				return file?.run { Paths.get(path).fileName.toString() } ?: "Invalid file"
+				return file?.run { Paths.get(path ?: return "Invalid file").fileName.toString() } ?: "Invalid file"
 			}
 
 		// TODO: URIs are bad

src/main/kotlin/link/infra/packwiz/installer/metadata/ManifestFile.kt

@@ -1,15 +1,15 @@
 package link.infra.packwiz.installer.metadata
 
 import com.google.gson.annotations.JsonAdapter
-import link.infra.packwiz.installer.UpdateManager
 import link.infra.packwiz.installer.metadata.hash.Hash
+import link.infra.packwiz.installer.target.Side
 
 class ManifestFile {
 	var packFileHash: Hash? = null
 	var indexFileHash: Hash? = null
 	var cachedFiles: MutableMap<SpaceSafeURI, File> = HashMap()
 	// If the side changes, EVERYTHING invalidates. FUN!!!
-	var cachedSide = UpdateManager.Options.Side.CLIENT
+	var cachedSide = Side.CLIENT
 
 	// TODO: switch to Kotlin-friendly JSON/TOML libs?
 	class File {

src/main/kotlin/link/infra/packwiz/installer/metadata/ModFile.kt

@@ -1,17 +1,20 @@
 package link.infra.packwiz.installer.metadata
 
+import com.google.gson.annotations.JsonAdapter
 import com.google.gson.annotations.SerializedName
-import link.infra.packwiz.installer.UpdateManager
+import link.infra.packwiz.installer.metadata.curseforge.UpdateData
+import link.infra.packwiz.installer.metadata.curseforge.UpdateDeserializer
 import link.infra.packwiz.installer.metadata.hash.Hash
 import link.infra.packwiz.installer.metadata.hash.HashUtils.getHash
 import link.infra.packwiz.installer.request.HandlerManager.getFileSource
 import link.infra.packwiz.installer.request.HandlerManager.getNewLoc
+import link.infra.packwiz.installer.target.Side
 import okio.Source
 
 class ModFile {
 	var name: String? = null
 	var filename: String? = null
-	var side: UpdateManager.Options.Side? = null
+	var side: Side? = null
 	var download: Download? = null
 
 	class Download {
@@ -19,11 +22,16 @@ class ModFile {
 		@SerializedName("hash-format")
 		var hashFormat: String? = null
 		var hash: String? = null
+		var mode: String? = null
 	}
 
-	var update: Map<String, Any>? = null
+	@JsonAdapter(UpdateDeserializer::class)
+	var update: Map<String, UpdateData>? = null
 	var option: Option? = null
 
+	@Transient
+	val resolvedUpdateData = mutableMapOf<String, SpaceSafeURI>()
+
 	class Option {
 		var optional = false
 		var description: String? = null
@@ -34,11 +42,20 @@ class ModFile {
 	@Throws(Exception::class)
 	fun getSource(baseLoc: SpaceSafeURI?): Source {
 		download?.let {
-			if (it.url == null) {
-				throw Exception("Metadata file doesn't have a download URI")
+			if (it.mode == null || it.mode == "" || it.mode == "url") {
+				if (it.url == null) {
+					throw Exception("Metadata file doesn't have a download URI")
+				}
+				val newLoc = getNewLoc(baseLoc, it.url) ?: throw Exception("Metadata file URI is invalid")
+				return getFileSource(newLoc)
+			} else if (it.mode == "metadata:curseforge") {
+				if (!resolvedUpdateData.contains("curseforge")) {
+					throw Exception("Metadata file specifies CurseForge mode, but is missing metadata")
+				}
+				return getFileSource(resolvedUpdateData["curseforge"]!!)
+			} else {
+				throw Exception("Unsupported download mode " + it.mode)
 			}
-			val newLoc = getNewLoc(baseLoc, it.url) ?: throw Exception("Metadata file URI is invalid")
-			return getFileSource(newLoc)
 		} ?: throw Exception("Metadata file doesn't have download")
 	}
 

src/main/kotlin/link/infra/packwiz/installer/metadata/PackFile.kt

@@ -14,6 +14,4 @@ class PackFile {
 	}
 
 	var versions: Map<String, String>? = null
-	var client: Map<String, Any>? = null
-	var server: Map<String, Any>? = null
 }

src/main/kotlin/link/infra/packwiz/installer/metadata/SpaceSafeURI.kt

@@ -32,7 +32,7 @@ class SpaceSafeURI : Comparable<SpaceSafeURI>, Serializable {
 		)
 	}
 
-	val path: String get() = u.path.replace("%20", " ")
+	val path: String? get() = u.path?.replace("%20", " ")
 
 	override fun toString(): String = u.toString().replace("%20", " ")
 
@@ -52,9 +52,9 @@ class SpaceSafeURI : Comparable<SpaceSafeURI>, Serializable {
 
 	override fun compareTo(other: SpaceSafeURI): Int = u.compareTo(other.u)
 
-	val scheme: String get() = u.scheme
-	val authority: String get() = u.authority
-	val host: String get() = u.host
+	val scheme: String? get() = u.scheme
+	val authority: String? get() = u.authority
+	val host: String? get() = u.host
 
 	@Throws(MalformedURLException::class)
 	fun toURL(): URL = u.toURL()

src/main/kotlin/link/infra/packwiz/installer/metadata/curseforge/CurseForgeSourcer.kt

@@ -0,0 +1,132 @@
+package link.infra.packwiz.installer.metadata.curseforge
+
+import com.google.gson.Gson
+import com.google.gson.JsonIOException
+import com.google.gson.JsonSyntaxException
+import link.infra.packwiz.installer.metadata.IndexFile
+import link.infra.packwiz.installer.metadata.SpaceSafeURI
+import link.infra.packwiz.installer.target.ClientHolder
+import link.infra.packwiz.installer.ui.data.ExceptionDetails
+import okhttp3.MediaType.Companion.toMediaType
+import okhttp3.Request
+import okhttp3.RequestBody.Companion.toRequestBody
+import okhttp3.internal.closeQuietly
+import okio.ByteString.Companion.decodeBase64
+import java.nio.charset.StandardCharsets
+
+private class GetFilesRequest(val fileIds: List<Int>)
+private class GetModsRequest(val modIds: List<Int>)
+
+private class GetFilesResponse {
+	class CfFile {
+		var id = 0
+		var modId = 0
+		var downloadUrl: SpaceSafeURI? = null
+	}
+	val data = mutableListOf<CfFile>()
+}
+
+private class GetModsResponse {
+	class CfMod {
+		var id = 0
+		var name = ""
+		var links: CfLinks? = null
+	}
+	class CfLinks {
+		var websiteUrl = ""
+	}
+	val data = mutableListOf<CfMod>()
+}
+
+private const val APIServer = "api.curseforge.com"
+// If you fork/derive from packwiz, I request that you obtain your own API key.
+private val APIKey = "JDJhJDEwJHNBWVhqblU1N0EzSmpzcmJYM3JVdk92UWk2NHBLS3BnQ2VpbGc1TUM1UGNKL0RYTmlGWWxh".decodeBase64()!!
+	.string(StandardCharsets.UTF_8)
+
+private val clientHolder = ClientHolder()
+
+// TODO: switch to PackwizPath stuff and OkHttp in old code
+
+@Throws(JsonSyntaxException::class, JsonIOException::class)
+fun resolveCfMetadata(mods: List<IndexFile.File>): List<ExceptionDetails> {
+	val failures = mutableListOf<ExceptionDetails>()
+	val fileIdMap = mutableMapOf<Int, IndexFile.File>()
+
+	for (mod in mods) {
+		if (mod.linkedFile!!.update == null) {
+			failures.add(ExceptionDetails(mod.linkedFile!!.name ?: mod.linkedFile!!.filename!!, Exception("Failed to resolve CurseForge metadata: no update section")))
+			continue
+		}
+		if (!mod.linkedFile!!.update!!.contains("curseforge")) {
+			failures.add(ExceptionDetails(mod.linkedFile!!.name ?: mod.linkedFile!!.filename!!, Exception("Failed to resolve CurseForge metadata: no CurseForge update section")))
+			continue
+		}
+		fileIdMap[(mod.linkedFile!!.update!!["curseforge"] as CurseForgeUpdateData).fileId] = mod
+	}
+
+	val reqData = GetFilesRequest(fileIdMap.keys.toList())
+	val req = Request.Builder()
+		.url("https://${APIServer}/v1/mods/files")
+		.header("Accept", "application/json")
+		.header("User-Agent", "packwiz-installer")
+		.header("X-API-Key", APIKey)
+		.post(Gson().toJson(reqData, GetFilesRequest::class.java).toRequestBody("application/json".toMediaType()))
+		.build()
+	val res = clientHolder.okHttpClient.newCall(req).execute()
+	if (!res.isSuccessful || res.body == null) {
+		res.closeQuietly()
+		failures.add(ExceptionDetails("Other", Exception("Failed to resolve CurseForge metadata for file data: error code ${res.code}")))
+		return failures
+	}
+
+	val resData = Gson().fromJson(res.body!!.charStream(), GetFilesResponse::class.java)
+	res.closeQuietly()
+
+	val manualDownloadMods = mutableMapOf<Int, Pair<IndexFile.File, Int>>()
+	for (file in resData.data) {
+		if (!fileIdMap.contains(file.id)) {
+			failures.add(ExceptionDetails(file.id.toString(),
+				Exception("Failed to find file from result: ID ${file.id}, Project ID ${file.modId}")))
+			continue
+		}
+		if (file.downloadUrl == null) {
+			manualDownloadMods[file.modId] = Pair(fileIdMap[file.id]!!, file.id)
+			continue
+		}
+		fileIdMap[file.id]!!.linkedFile!!.resolvedUpdateData["curseforge"] = file.downloadUrl!!
+	}
+
+	if (manualDownloadMods.isNotEmpty()) {
+		val reqModsData = GetModsRequest(manualDownloadMods.keys.toList())
+		val reqMods = Request.Builder()
+			.url("https://${APIServer}/v1/mods")
+			.header("Accept", "application/json")
+			.header("User-Agent", "packwiz-installer")
+			.header("X-API-Key", APIKey)
+			.post(Gson().toJson(reqModsData, GetModsRequest::class.java).toRequestBody("application/json".toMediaType()))
+			.build()
+		val resMods = clientHolder.okHttpClient.newCall(reqMods).execute()
+		if (!resMods.isSuccessful || resMods.body == null) {
+			resMods.closeQuietly()
+			failures.add(ExceptionDetails("Other", Exception("Failed to resolve CurseForge metadata for mod data: error code ${resMods.code}")))
+			return failures
+		}
+
+		val resModsData = Gson().fromJson(resMods.body!!.charStream(), GetModsResponse::class.java)
+		resMods.closeQuietly()
+
+		for (mod in resModsData.data) {
+			if (!manualDownloadMods.contains(mod.id)) {
+				failures.add(ExceptionDetails(mod.name,
+					Exception("Failed to find project from result: ID ${mod.id}")))
+				continue
+			}
+
+			val modFile = manualDownloadMods[mod.id]!!
+			failures.add(ExceptionDetails(mod.name, Exception("This mod is excluded from the CurseForge API and must be downloaded manually.\n" +
+				"Please go to ${mod.links?.websiteUrl}/files/${modFile.second} and save this file to ${modFile.first.destURI}")))
+		}
+	}
+
+	return failures
+}

src/main/kotlin/link/infra/packwiz/installer/metadata/curseforge/CurseForgeUpdateData.kt

@@ -0,0 +1,10 @@
+package link.infra.packwiz.installer.metadata.curseforge
+
+import com.google.gson.annotations.SerializedName
+
+class CurseForgeUpdateData: UpdateData {
+	@SerializedName("file-id")
+	var fileId = 0
+	@SerializedName("project-id")
+	var projectId = 0
+}

src/main/kotlin/link/infra/packwiz/installer/metadata/curseforge/UpdateData.kt

@@ -0,0 +1,3 @@
+package link.infra.packwiz.installer.metadata.curseforge
+
+interface UpdateData

src/main/kotlin/link/infra/packwiz/installer/metadata/curseforge/UpdateDeserializer.kt

@@ -0,0 +1,22 @@
+package link.infra.packwiz.installer.metadata.curseforge
+
+import com.google.gson.JsonDeserializationContext
+import com.google.gson.JsonDeserializer
+import com.google.gson.JsonElement
+import java.lang.reflect.Type
+
+class UpdateDeserializer: JsonDeserializer<Map<String, UpdateData>> {
+	override fun deserialize(
+		json: JsonElement?,
+		typeOfT: Type?,
+		context: JsonDeserializationContext?
+	): Map<String, UpdateData> {
+		val out = mutableMapOf<String, UpdateData>()
+		for ((k, v) in json!!.asJsonObject.entrySet()) {
+			if (k == "curseforge") {
+				out[k] = context!!.deserialize(v, CurseForgeUpdateData::class.java)
+			}
+		}
+		return out
+	}
+}

src/main/kotlin/link/infra/packwiz/installer/request/RequestExceptions.kt

@@ -0,0 +1,70 @@
+package link.infra.packwiz.installer.request
+
+import okhttp3.Response
+import okio.IOException
+
+sealed class RequestException: Exception {
+	constructor(message: String, cause: Throwable) : super(message, cause)
+	constructor(message: String) : super(message)
+
+	/**
+	 * Internal errors that should not be shown to the user when the code is correct
+	 */
+	sealed class Internal: RequestException {
+		constructor(message: String, cause: Throwable) : super(message, cause)
+		constructor(message: String) : super(message)
+
+		class UnsinkableBase: Internal("Base associated with this path is not a SinkableBase")
+
+		sealed class HTTP: Internal {
+			constructor(message: String, cause: Throwable) : super(message, cause)
+			constructor(message: String) : super(message)
+
+			class NoResponseBody: HTTP("HTTP response in onResponse must have a response body")
+			class RequestFailed(cause: IOException): HTTP("HTTP request failed; may have been cancelled", cause)
+			class IllegalState(cause: IllegalStateException): HTTP("Internal fatal HTTP request error", cause)
+		}
+	}
+
+	/**
+	 * Errors indicating that the request is malformed
+	 */
+	sealed class Validation: RequestException {
+		constructor(message: String, cause: Throwable) : super(message, cause)
+		constructor(message: String) : super(message)
+
+		// TODO: move out of RequestException?
+		class PathContainsNUL(path: String): Validation("Invalid path; contains NUL bytes: ${path.replace("\u0000", "")}")
+		class PathContainsVolumeLetter(path: String): Validation("Invalid path; contains volume letter: $path")
+	}
+
+	/**
+	 * Errors relating to the response from the server
+	 */
+	sealed class Response: RequestException {
+		constructor(message: String, cause: Throwable) : super(message, cause)
+		constructor(message: String) : super(message)
+
+		// TODO: fancier way of displaying this?
+		sealed class HTTP: Response {
+			val response: okhttp3.Response
+
+			constructor(response: okhttp3.Response, message: String, cause: Throwable) : super(message, cause) {
+				this.response = response
+			}
+			constructor(response: okhttp3.Response, message: String) : super(message) {
+				this.response = response
+			}
+
+			class ErrorCode(res: okhttp3.Response): HTTP(res, "Non-successful error code from HTTP request: ${res.code}")
+		}
+
+		sealed class File: RequestException {
+			constructor(message: String, cause: Throwable) : super(message, cause)
+			constructor(message: String) : super(message)
+
+			class FileNotFound(file: String): File("File path not found: $file")
+			class Other(cause: Throwable): File("Failed to read file", cause)
+		}
+	}
+}

src/main/kotlin/link/infra/packwiz/installer/request/handlers/RequestHandlerGithub.kt

@@ -1,7 +1,6 @@
 package link.infra.packwiz.installer.request.handlers
 
 import link.infra.packwiz.installer.metadata.SpaceSafeURI
-import java.util.*
 import java.util.concurrent.locks.ReentrantReadWriteLock
 import java.util.regex.Pattern
 import kotlin.concurrent.read
@@ -21,7 +20,7 @@ class RequestHandlerGithub : RequestHandlerZip(true) {
 	private val zipUriMap: MutableMap<String, SpaceSafeURI> = HashMap()
 	private val zipUriLock = ReentrantReadWriteLock()
 	private fun getRepoName(loc: SpaceSafeURI): String? {
-		val matcher = repoMatcherPattern.matcher(loc.path)
+		val matcher = repoMatcherPattern.matcher(loc.path ?: return null)
 		return if (matcher.matches()) {
 			matcher.group(1)
 		} else {
@@ -47,7 +46,7 @@ class RequestHandlerGithub : RequestHandlerZip(true) {
 	}
 
 	private fun getBranch(loc: SpaceSafeURI): String? {
-		val matcher = branchMatcherPattern.matcher(loc.path)
+		val matcher = branchMatcherPattern.matcher(loc.path ?: return null)
 		return if (matcher.matches()) {
 			matcher.group(1)
 		} else {
@@ -66,6 +65,6 @@ class RequestHandlerGithub : RequestHandlerZip(true) {
 			return false
 		}
 		// TODO: more match testing?
-		return "github.com" == loc.host && branchMatcherPattern.matcher(loc.path).matches()
+		return "github.com" == loc.host && branchMatcherPattern.matcher(loc.path ?: return false).matches()
 	}
 }

src/main/kotlin/link/infra/packwiz/installer/target/CachedTarget.kt

@@ -0,0 +1,23 @@
+package link.infra.packwiz.installer.target
+
+import link.infra.packwiz.installer.metadata.hash.Hash
+import java.nio.file.Path
+
+data class CachedTarget(
+	/**
+	 * @see Target.name
+	 */
+	val name: String,
+	/**
+	 * The location where the target was last downloaded to.
+	 * This is used for removing old files when the destination path changes.
+	 * This shouldn't be set to the .disabled path (that is manually appended and checked)
+	 */
+	val cachedLocation: Path,
+	val enabled: Boolean,
+	val hash: Hash,
+	/**
+	 * For detecting when a target transitions non-optional -> optional and showing the option selection screen
+	 */
+	val isOptional: Boolean
+)

src/main/kotlin/link/infra/packwiz/installer/target/CachedTargetValidation.kt

@@ -0,0 +1,95 @@
+package link.infra.packwiz.installer.target
+
+import java.io.IOException
+import java.nio.file.*
+import java.nio.file.attribute.BasicFileAttributes
+import kotlin.io.path.relativeTo
+
+data class CachedTargetStatus(val target: CachedTarget, var isValid: Boolean, var markDisabled: Boolean)
+
+fun validate(targets: List<CachedTarget>, baseDir: Path) = runCatching {
+	val results = targets.map {
+		CachedTargetStatus(it, isValid = false, markDisabled = false)
+	}
+	val tree = buildTree(results, baseDir)
+
+	// Efficient file exists checking using directory listing, several orders of magnitude faster than Files.exists calls
+	Files.walkFileTree(baseDir, setOf(FileVisitOption.FOLLOW_LINKS), Int.MAX_VALUE, object : FileVisitor<Path> {
+		var currentNode: PathNode<CachedTargetStatus> = tree
+
+		override fun preVisitDirectory(dir: Path?, attrs: BasicFileAttributes?): FileVisitResult {
+			if (dir == null) {
+				return FileVisitResult.SKIP_SUBTREE
+			}
+			val subdirNode = currentNode.subdirs[dir.getName(dir.nameCount - 1)]
+			return if (subdirNode != null) {
+				currentNode = subdirNode
+				FileVisitResult.CONTINUE
+			} else {
+				FileVisitResult.SKIP_SUBTREE
+			}
+		}
+
+		override fun visitFile(file: Path?, attrs: BasicFileAttributes?): FileVisitResult {
+			if (file == null) {
+				return FileVisitResult.CONTINUE
+			}
+			// TODO: these are relative paths to baseDir
+			// TODO: strip the .disabled for lookup
+			val target = currentNode.files[file.getName(file.nameCount - 1)]
+			if (target != null) {
+				val disabledFile = file.endsWith(".disabled")
+				// If a .disabled file and the actual file both exist, mark as invalid if the target is disabled
+				if ((disabledFile )) {
+
+				}
+			}
+			return FileVisitResult.CONTINUE
+		}
+
+		@Throws(IOException::class)
+		override fun visitFileFailed(file: Path?, exc: IOException?): FileVisitResult {
+			if (exc != null) {
+				throw exc
+			}
+			throw IOException("visitFileFailed called with no exception")
+		}
+
+		@Throws(IOException::class)
+		override fun postVisitDirectory(dir: Path?, exc: IOException?): FileVisitResult {
+			if (exc != null) {
+				throw exc
+			} else {
+				val parent = currentNode.parent
+				if (parent != null) {
+					currentNode = parent
+				} else {
+					throw IOException("Invalid visitor tree structure")
+				}
+				return FileVisitResult.CONTINUE
+			}
+		}
+	})
+
+	results
+}
+
+fun buildTree(targets: List<CachedTargetStatus>, baseDir: Path): PathNode<CachedTargetStatus> {
+	val root = PathNode<CachedTargetStatus>()
+	for (target in targets) {
+		val relPath = target.target.cachedLocation.relativeTo(baseDir)
+		var node = root
+		// Traverse all the directory components, except for the last one
+		for (i in 0 until (relPath.nameCount - 1)) {
+			node = node.createSubdir(relPath.getName(i))
+		}
+		node.files[relPath.getName(relPath.nameCount - 1)] = target
+	}
+	return root
+}
+
+data class PathNode<T>(val subdirs: MutableMap<Path, PathNode<T>>, val files: MutableMap<Path, T>, val parent: PathNode<T>?) {
+	constructor() : this(mutableMapOf(), mutableMapOf(), null)
+
+	fun createSubdir(nextComponent: Path) = subdirs.getOrPut(nextComponent, { PathNode(mutableMapOf(), mutableMapOf(), this) })
+}

src/main/kotlin/link/infra/packwiz/installer/target/ClientHolder.kt

@@ -0,0 +1,12 @@
+package link.infra.packwiz.installer.target
+
+import okhttp3.OkHttpClient
+import okio.FileSystem
+
+class ClientHolder {
+	// TODO: timeouts?
+	// TODO: a button to increase timeouts temporarily when retrying?
+	val okHttpClient by lazy { OkHttpClient.Builder().build() }
+
+	val fileSystem = FileSystem.SYSTEM
+}

src/main/kotlin/link/infra/packwiz/installer/target/OverwriteMode.kt

@@ -0,0 +1,13 @@
+package link.infra.packwiz.installer.target
+
+enum class OverwriteMode {
+	/**
+	 * Overwrite the destination with the source file, if the source file has changed.
+	 */
+	IF_SRC_CHANGED,
+
+	/**
+	 * Never overwrite the destination; if it exists, it should not be written to.
+	 */
+	NEVER
+}

src/main/kotlin/link/infra/packwiz/installer/target/Side.kt

@@ -0,0 +1,54 @@
+package link.infra.packwiz.installer.target
+
+import com.google.gson.annotations.SerializedName
+
+enum class Side {
+	@SerializedName("client")
+	CLIENT("client"),
+	@SerializedName("server")
+	SERVER("server"),
+	@SerializedName("both")
+	@Suppress("unused")
+	BOTH("both", arrayOf(CLIENT, SERVER));
+
+	private val sideName: String
+	private val depSides: Array<Side>?
+
+	constructor(sideName: String) {
+		this.sideName = sideName.toLowerCase()
+		depSides = null
+	}
+
+	constructor(sideName: String, depSides: Array<Side>) {
+		this.sideName = sideName.toLowerCase()
+		this.depSides = depSides
+	}
+
+	override fun toString() = sideName
+
+	fun hasSide(tSide: Side): Boolean {
+		if (this == tSide) {
+			return true
+		}
+		if (depSides != null) {
+			for (depSide in depSides) {
+				if (depSide == tSide) {
+					return true
+				}
+			}
+		}
+		return false
+	}
+
+	companion object {
+		fun from(name: String): Side? {
+			val lowerName = name.toLowerCase()
+			for (side in values()) {
+				if (side.sideName == lowerName) {
+					return side
+				}
+			}
+			return null
+		}
+	}
+}

src/main/kotlin/link/infra/packwiz/installer/target/Target.kt

@@ -0,0 +1,45 @@
+package link.infra.packwiz.installer.target
+
+import link.infra.packwiz.installer.target.path.PackwizPath
+
+// TODO: rename to avoid conflicting with @Target
+interface Target {
+	val src: PackwizPath
+	val dest: PackwizPath
+	val validityToken: ValidityToken
+
+	/**
+	 * Token interface for types used to compare Target identity. Implementations should use equals to indicate that
+	 * these tokens represent the same file; used to preserve optional target choices between file renames.
+	 */
+	interface IdentityToken
+
+	/**
+	 * Default implementation of IdentityToken that assumes files are not renamed; so optional choices do not need to
+	 * be preserved across renames.
+	 */
+	@JvmInline
+	value class PathIdentityToken(val path: String): IdentityToken
+
+	val ident: IdentityToken
+		get() = PathIdentityToken(dest.path)
+
+	/**
+	 * A user-friendly name; defaults to the destination path of the file.
+	 */
+	val name: String
+		get() = dest.path
+	val side: Side
+		get() = Side.BOTH
+	val overwriteMode: OverwriteMode
+		get() = OverwriteMode.IF_SRC_CHANGED
+
+	interface Optional: Target {
+		val optional: Boolean
+		val optionalDefaultValue: Boolean
+	}
+
+	interface OptionalDescribed: Optional {
+		val optionalDescription: String
+	}
+}

src/main/kotlin/link/infra/packwiz/installer/target/ValidityToken.kt

@@ -0,0 +1,16 @@
+package link.infra.packwiz.installer.target
+
+import link.infra.packwiz.installer.metadata.hash.Hash
+
+/**
+ * A token used to determine if the source or destination file is changed, and ensure that the destination file is valid.
+ */
+interface ValidityToken {
+	// TODO: functions to allow validating this from file metadata, from file, or during the download process
+
+	/**
+	 * Default implementation of ValidityToken based on a single hash.
+	 */
+	@JvmInline
+	value class HashValidityToken(val hash: Hash): ValidityToken
+}

src/main/kotlin/link/infra/packwiz/installer/target/path/FilePathBase.kt

@@ -0,0 +1,29 @@
+package link.infra.packwiz.installer.target.path
+
+import link.infra.packwiz.installer.request.RequestException
+import link.infra.packwiz.installer.target.ClientHolder
+import okio.*
+
+data class FilePathBase(private val path: Path): PackwizPath.Base, PackwizPath.SinkableBase {
+	override fun source(path: String, clientHolder: ClientHolder): BufferedSource {
+		val resolved = this.path.resolve(path, true)
+		try {
+			return clientHolder.fileSystem.source(resolved).buffer()
+		} catch (e: FileNotFoundException) {
+			throw RequestException.Response.File.FileNotFound(resolved.toString())
+		} catch (e: IOException) {
+			throw RequestException.Response.File.Other(e)
+		}
+	}
+
+	override fun sink(path: String, clientHolder: ClientHolder): BufferedSink {
+		val resolved = this.path.resolve(path, true)
+		try {
+			return clientHolder.fileSystem.sink(resolved).buffer()
+		} catch (e: FileNotFoundException) {
+			throw RequestException.Response.File.FileNotFound(resolved.toString())
+		} catch (e: IOException) {
+			throw RequestException.Response.File.Other(e)
+		}
+	}
+}

src/main/kotlin/link/infra/packwiz/installer/target/path/HttpUrlBase.kt

@@ -0,0 +1,41 @@
+package link.infra.packwiz.installer.target.path
+
+import link.infra.packwiz.installer.request.RequestException
+import link.infra.packwiz.installer.target.ClientHolder
+import okhttp3.HttpUrl
+import okhttp3.Request
+import okio.BufferedSource
+import okio.IOException
+
+data class HttpUrlBase(private val url: HttpUrl): PackwizPath.Base {
+	private fun resolve(path: String) = url.newBuilder().addPathSegments(path).build()
+
+	override fun source(path: String, clientHolder: ClientHolder): BufferedSource {
+		val req = Request.Builder()
+			.url(resolve(path))
+			.header("Accept", "application/octet-stream")
+			.header("User-Agent", "packwiz-installer")
+			.get()
+			.build()
+		try {
+			val res = clientHolder.okHttpClient.newCall(req).execute()
+			// Can't use .use since it would close the response body before returning it to the caller
+			try {
+				if (!res.isSuccessful) {
+					throw RequestException.Response.HTTP.ErrorCode(res)
+				}
+
+				val body = res.body ?: throw RequestException.Internal.HTTP.NoResponseBody()
+				return body.source()
+			} catch (e: Exception) {
+				// If an exception is thrown, close the response and rethrow
+				res.close()
+				throw e
+			}
+		} catch (e: IOException) {
+			throw RequestException.Internal.HTTP.RequestFailed(e)
+		} catch (e: IllegalStateException) {
+			throw RequestException.Internal.HTTP.IllegalState(e)
+		}
+	}
+}

src/main/kotlin/link/infra/packwiz/installer/target/path/PackwizPath.kt

@@ -0,0 +1,124 @@
+package link.infra.packwiz.installer.target.path
+
+import link.infra.packwiz.installer.request.RequestException
+import link.infra.packwiz.installer.target.ClientHolder
+import okio.BufferedSink
+import okio.BufferedSource
+
+class PackwizPath(path: String, base: Base) {
+	val path: String
+	val base: Base
+
+	init {
+		this.base = base
+
+		// Check for NUL bytes
+		if (path.contains('\u0000')) { throw RequestException.Validation.PathContainsNUL(path) }
+		// Normalise separator, to prevent differences between Unix/Windows
+		val pathNorm = path.replace('\\', '/')
+		// Split, create new lists for output
+		val split = pathNorm.split('/')
+		val canonicalised = mutableListOf<String>()
+
+		// Backward pass: collapse ".." components, remove "." components and empty components (except an empty component at the end; indicating a folder)
+		var parentComponentCount = 0
+		var first = true
+		for (component in split.asReversed()) {
+			if (first) {
+				first = false
+				if (component == "") {
+					canonicalised += component
+				}
+			}
+			// URL-encoded . is normalised
+			val componentNorm = component.replace("%2e", ".")
+			if (componentNorm == "." || componentNorm == "") {
+				// Do nothing
+			} else if (componentNorm == "..") {
+				parentComponentCount++
+			} else if (parentComponentCount > 0) {
+				parentComponentCount--
+			} else {
+				canonicalised += componentNorm
+				// Don't allow volume letters (allows traversal to the root on Windows)
+				if (componentNorm[0] in 'a'..'z' || componentNorm[0] in 'A'..'Z') {
+					if (componentNorm[1] == ':') {
+						throw RequestException.Validation.PathContainsVolumeLetter(path)
+					}
+				}
+			}
+		}
+
+		// Join path
+		this.path = canonicalised.asReversed().joinToString("/")
+	}
+
+	val folder: Boolean get() = path.endsWith("/")
+
+	fun resolve(path: String): PackwizPath {
+		return if (path.startsWith('/') || path.startsWith('\\')) {
+			// Absolute (but still relative to base of pack)
+			PackwizPath(path, base)
+		} else if (folder) {
+			// File in folder; append
+			PackwizPath(this.path + path, base)
+		} else {
+			// File in parent folder; append with parent component
+			PackwizPath(this.path + "/../" + path, base)
+		}
+	}
+
+	/**
+	 * Obtain a BufferedSource for this path
+	 * @throws RequestException When resolving the file failed
+	 */
+	fun source(clientHolder: ClientHolder): BufferedSource = base.source(path, clientHolder)
+
+	/**
+	 * Obtain a BufferedSink for this path
+	 * @throws RequestException.Internal.UnsinkableBase When the base of this path does not have a sink
+	 * @throws RequestException When resolving the file failed
+	 */
+	fun sink(clientHolder: ClientHolder): BufferedSink =
+		if (base is SinkableBase) { base.sink(path, clientHolder) } else { throw RequestException.Internal.UnsinkableBase() }
+
+	interface Base {
+		/**
+		 * Resolve the given (canonical) path against the base, and get a BufferedSource for this file.
+		 * @throws RequestException
+		 */
+		fun source(path: String, clientHolder: ClientHolder): BufferedSource
+
+		operator fun div(path: String) = PackwizPath(path, this)
+	}
+
+	interface SinkableBase: Base {
+		/**
+		 * Resolve the given (canonical) path against the base, and get a BufferedSink for this file.
+		 * @throws RequestException
+		 */
+		fun sink(path: String, clientHolder: ClientHolder): BufferedSink
+	}
+
+	override fun equals(other: Any?): Boolean {
+		if (this === other) return true
+		if (javaClass != other?.javaClass) return false
+
+		other as PackwizPath
+
+		if (path != other.path) return false
+		if (base != other.base) return false
+
+		return true
+	}
+
+	override fun hashCode(): Int {
+		var result = path.hashCode()
+		result = 31 * result + base.hashCode()
+		return result
+	}
+
+	override fun toString(): String {
+		return "base=$base; $path"
+	}
+}

src/main/kotlin/link/infra/packwiz/installer/task/CacheKey.kt

@@ -0,0 +1,3 @@
+package link.infra.packwiz.installer.task
+
+data class CacheKey<T>(val key: String, val version: Int)

src/main/kotlin/link/infra/packwiz/installer/task/CacheManager.kt

@@ -0,0 +1,22 @@
+package link.infra.packwiz.installer.task
+
+import kotlin.reflect.KProperty
+
+class CacheManager {
+	class CacheValue<T> {
+		operator fun getValue(thisVal: Any?, property: KProperty<*>): T {
+			TODO("Not yet implemented")
+		}
+
+		operator fun setValue(thisVal: Any?, property: KProperty<*>, value: T) {
+			TODO("Not yet implemented")
+		}
+
+	}
+
+	operator fun <T> get(cacheKey: CacheKey<T>): CacheValue<T> {
+		return CacheValue()
+	}
+
+
+}

src/main/kotlin/link/infra/packwiz/installer/task/Task.kt

@@ -0,0 +1,20 @@
+package link.infra.packwiz.installer.task
+
+import kotlin.reflect.KMutableProperty0
+
+// TODO: task processing on 1 background thread; actual resolving of values calls out to a thread group
+// TODO: progress bar is updated from each of these tasks
+// TODO: have everything be lazy so there's no need to determine task ordering upfront? a bit like rust async - task results must be queried to occur
+
+abstract class Task<T>(protected val ctx: TaskContext): TaskInput<T> {
+	// TODO: lazy wrapper for fallible results
+	// TODO: multithreaded fanout subclass/helper
+
+	protected fun <T> wasUpdated(value: KMutableProperty0<T>, newValue: T): Boolean {
+		if (value.get() == newValue) {
+			return false
+		}
+		value.set(newValue)
+		return true
+	}
+}

src/main/kotlin/link/infra/packwiz/installer/task/TaskCombinedResult.kt

@@ -0,0 +1,6 @@
+package link.infra.packwiz.installer.task
+
+/**
+ * An object for storing results where result and upToDate are calculated simultaneously
+ */
+data class TaskCombinedResult<T>(val result: T, val upToDate: Boolean)

src/main/kotlin/link/infra/packwiz/installer/task/TaskContext.kt

@@ -0,0 +1,12 @@
+package link.infra.packwiz.installer.task
+
+import link.infra.packwiz.installer.target.ClientHolder
+
+class TaskContext {
+	// TODO: thread pools, protocol roots
+	// TODO: cache management
+
+	val cache = CacheManager()
+
+	val clients = ClientHolder()
+}

src/main/kotlin/link/infra/packwiz/installer/task/TaskInput.kt

@@ -0,0 +1,29 @@
+package link.infra.packwiz.installer.task
+
+import kotlin.reflect.KProperty
+
+interface TaskInput<T> {
+	/**
+	 * The value of this task input. May be lazily evaluated; must be threadsafe.
+	 */
+	val value: T
+
+	/**
+	 * True if the effective value of this input has changed since the task was last run.
+	 * Doesn't require evaluation of the input value; should use cached data if possible.
+	 * May be lazily evaluated; must be threadsafe.
+	 */
+	val upToDate: Boolean
+
+	operator fun getValue(thisVal: Any?, property: KProperty<*>): T = value
+
+	companion object {
+		fun <T> raw(value: T): TaskInput<T> {
+			return object: TaskInput<T> {
+				override val value = value
+				override val upToDate: Boolean
+					get() = false
+			}
+		}
+	}
+}

src/main/kotlin/link/infra/packwiz/installer/task/formats/packwizv1/PackwizV1PackFile.kt

@@ -0,0 +1,6 @@
+package link.infra.packwiz.installer.task.formats.packwizv1
+
+import link.infra.packwiz.installer.metadata.hash.Hash
+import link.infra.packwiz.installer.target.path.PackwizPath
+
+data class PackwizV1PackFile(val name: String, val indexPath: PackwizPath, val indexHash: Hash)

src/main/kotlin/link/infra/packwiz/installer/task/formats/packwizv1/PackwizV1PackTomlTask.kt

@@ -0,0 +1,48 @@
+package link.infra.packwiz.installer.task.formats.packwizv1
+
+import com.google.gson.annotations.SerializedName
+import com.moandjiezana.toml.Toml
+import link.infra.packwiz.installer.metadata.hash.Hash
+import link.infra.packwiz.installer.metadata.hash.HashUtils
+import link.infra.packwiz.installer.target.path.PackwizPath
+import link.infra.packwiz.installer.task.CacheKey
+import link.infra.packwiz.installer.task.Task
+import link.infra.packwiz.installer.task.TaskCombinedResult
+import link.infra.packwiz.installer.task.TaskContext
+import java.io.InputStreamReader
+
+class PackwizV1PackTomlTask(ctx: TaskContext, val path: PackwizPath): Task<PackwizV1PackFile>(ctx) {
+	// TODO: make hierarchically defined by caller? - then changing the pack format type doesn't leave junk in the cache
+	private var cache by ctx.cache[CacheKey<Hash>("packwiz.v1.packtoml.hash", 1)]
+
+	private class PackFile {
+		var name: String? = null
+		var index: IndexFileLoc? = null
+
+		class IndexFileLoc {
+			var file: String? = null
+			@SerializedName("hash-format")
+			var hashFormat: String? = null
+			var hash: String? = null
+		}
+
+		var versions: Map<String, String>? = null
+	}
+
+	private val internalResult by lazy {
+		// TODO: query, parse JSON
+		val packFile = Toml().read(InputStreamReader(path.source(ctx.clients).inputStream(), "UTF-8")).to(PackFile::class.java)
+
+		val resolved = PackwizV1PackFile(packFile.name ?: throw RuntimeException("Name required"), // TODO: better exception handling
+			path.resolve(packFile.index?.file ?: throw RuntimeException("File required")),
+			HashUtils.getHash(packFile.index?.hashFormat ?: throw RuntimeException("Hash format required"),
+				packFile.index?.hash ?: throw RuntimeException("Hash required"))
+		)
+		val hash = HashUtils.getHash("sha256", "whatever was just read")
+
+		TaskCombinedResult(resolved, wasUpdated(::cache, hash))
+	}
+
+	override val value by internalResult::result
+	override val upToDate by internalResult::upToDate
+}

src/main/kotlin/link/infra/packwiz/installer/ui/IUserInterface.kt

@@ -23,6 +23,8 @@ interface IUserInterface {
 
 	fun showCancellationDialog(): CancellationResult = CancellationResult.QUIT
 
+	fun awaitOptionalButton(showCancel: Boolean)
+
 	enum class ExceptionListResult {
 		CONTINUE, CANCEL, IGNORE
 	}

src/main/kotlin/link/infra/packwiz/installer/ui/cli/CLIHandler.kt

@@ -59,4 +59,8 @@ class CLIHandler : IUserInterface {
 		}
 		return ExceptionListResult.CANCEL
 	}
+
+	override fun awaitOptionalButton(showCancel: Boolean) {
+		// Do nothing
+	}
 }

src/main/kotlin/link/infra/packwiz/installer/ui/gui/ExceptionListWindow.kt

@@ -125,7 +125,7 @@ class ExceptionListWindow(eList: List<ExceptionDetails>, future: CompletableFutu
 						if (Desktop.isDesktopSupported() && Desktop.getDesktop().isSupported(Desktop.Action.BROWSE)) {
 							addActionListener {
 								try {
-									Desktop.getDesktop().browse(URI("https://github.com/comp500/packwiz-installer/issues/new"))
+									Desktop.getDesktop().browse(URI("https://github.com/packwiz/packwiz-installer/issues/new"))
 								} catch (e: IOException) {
 									// lol the button just won't work i guess
 								} catch (e: URISyntaxException) {}

src/main/kotlin/link/infra/packwiz/installer/ui/gui/GUIHandler.kt

@@ -8,6 +8,7 @@ import link.infra.packwiz.installer.ui.data.InstallProgress
 import link.infra.packwiz.installer.util.Log
 import java.awt.EventQueue
 import java.util.concurrent.CompletableFuture
+import java.util.concurrent.CountDownLatch
 import javax.swing.JDialog
 import javax.swing.JOptionPane
 import javax.swing.UIManager
@@ -18,8 +19,21 @@ class GUIHandler : IUserInterface {
 
 	@Volatile
 	override var optionsButtonPressed = false
+		set(value) {
+			optionalSelectedLatch.countDown()
+			field = value
+		}
 	@Volatile
 	override var cancelButtonPressed = false
+		set(value) {
+			optionalSelectedLatch.countDown()
+			field = value
+		}
+	var okButtonPressed = false
+		set(value) {
+			optionalSelectedLatch.countDown()
+			field = value
+		}
 	@Volatile
 	override var firstInstall = false
 
@@ -42,8 +56,12 @@ class GUIHandler : IUserInterface {
 		}
 	}
 
+	private val visibleCountdownLatch = CountDownLatch(1)
+	private val optionalSelectedLatch = CountDownLatch(1)
+
 	override fun show() = EventQueue.invokeLater {
 		frmPackwizlauncher.isVisible = true
+		visibleCountdownLatch.countDown()
 	}
 
 	override fun dispose() = EventQueue.invokeAndWait {
@@ -147,4 +165,15 @@ class GUIHandler : IUserInterface {
 		}
 		return future.get()
 	}
+
+	override fun awaitOptionalButton(showCancel: Boolean) {
+		EventQueue.invokeAndWait {
+			frmPackwizlauncher.showOk(!showCancel)
+		}
+		visibleCountdownLatch.await()
+		optionalSelectedLatch.await()
+		EventQueue.invokeLater {
+			frmPackwizlauncher.hideOk()
+		}
+	}
 }

src/main/kotlin/link/infra/packwiz/installer/ui/gui/InstallWindow.kt

@@ -12,6 +12,9 @@ class InstallWindow(private val handler: GUIHandler) : JFrame() {
 	private var lblProgresslabel: JLabel
 	private var progressBar: JProgressBar
 	private var btnOptions: JButton
+	private val btnCancel: JButton
+	private val btnOk: JButton
+	private val buttonsPanel: JPanel
 
 	init {
 		setBounds(100, 100, 493, 95)
@@ -35,7 +38,7 @@ class InstallWindow(private val handler: GUIHandler) : JFrame() {
 		}, BorderLayout.CENTER)
 
 		// Buttons
-		add(JPanel().apply {
+		buttonsPanel = JPanel().apply {
 			border = EmptyBorder(0, 5, 0, 5)
 			layout = GridBagLayout()
 
@@ -49,20 +52,28 @@ class InstallWindow(private val handler: GUIHandler) : JFrame() {
 				}
 			}
 			add(btnOptions, GridBagConstraints().apply {
-				gridx = 0
+				gridx = 1
 				gridy = 0
 			})
 
-			add(JButton("Cancel").apply {
+			btnCancel = JButton("Cancel").apply {
 				addActionListener {
 					isEnabled = false
 					handler.cancelButtonPressed = true
 				}
-			}, GridBagConstraints().apply {
-				gridx = 0
+			}
+			add(btnCancel, GridBagConstraints().apply {
+				gridx = 1
 				gridy = 1
 			})
-		}, BorderLayout.EAST)
+		}
+
+		btnOk = JButton("Continue").apply {
+			addActionListener {
+				handler.okButtonPressed = true
+			}
+		}
+		add(buttonsPanel, BorderLayout.EAST)
 	}
 
 	fun displayProgress(progress: InstallProgress) {
@@ -83,4 +94,31 @@ class InstallWindow(private val handler: GUIHandler) : JFrame() {
  			isEnabled = false
 		}
 	}
+
+	fun showOk(hideCancel: Boolean) {
+		if (hideCancel) {
+			buttonsPanel.add(btnOk, GridBagConstraints().apply {
+				gridx = 1
+				gridy = 1
+			})
+			buttonsPanel.remove(btnCancel)
+		} else {
+			buttonsPanel.add(btnOk, GridBagConstraints().apply {
+				gridx = 0
+				gridy = 1
+			})
+		}
+		buttonsPanel.revalidate()
+	}
+
+	fun hideOk() {
+		buttonsPanel.remove(btnOk)
+		if (!buttonsPanel.components.contains(btnCancel)) {
+			buttonsPanel.add(btnCancel, GridBagConstraints().apply {
+				gridx = 1
+				gridy = 1
+			})
+		}
+		buttonsPanel.revalidate()
+	}
 }

src/main/resources/META-INF/LICENSES.md

@@ -1,14 +1,22 @@
 # Licenses
 
-packwiz-installer itself is under the MIT license, except for Murmur2Lib and bundled dependencies as follows:
+packwiz-installer itself is under the MIT license ([Source](https://github.com/packwiz/packwiz-installer)), except for Murmur2Lib and bundled dependencies as follows:
 
 - Murmur2Lib: Apache 2.0 ([Source](https://github.com/prasanthj/hasher/blob/master/src/main/java/hasher/Murmur2.java))
-- Google Gson 2.8.1: Apache 2.0 ([Source](https://github.com/google/gson))
-- Okio 2.9.0: Apache 2.0 ([Source](https://github.com/square/okio/))
-- Commons CLI 1.4: Apache 2.0 ([Source](http://commons.apache.org/proper/commons-cli/))
+  - Copyright 2014 Prasanth Jayachandran
+- Google Gson 2.8.9: Apache 2.0 ([Source](https://github.com/google/gson))
+  - Copyright 2008 Google Inc.
+- Okio 3.0.0: Apache 2.0 ([Source](https://github.com/square/okio/))
+  - Copyright 2013 Square, Inc.
+- Commons CLI 1.5: Apache 2.0 ([Source](http://commons.apache.org/proper/commons-cli/))
 - Jetbrains Annotations 13.0: Apache 2.0 ([Source](https://github.com/JetBrains/java-annotations))
-- Kotlin Standard Library 1.4.21: Apache 2.0 ([Source](https://github.com/JetBrains/kotlin))
+  - Copyright 2000-2016 JetBrains s.r.o.
+- Kotlin Standard Library 1.6.10: Apache 2.0 ([Source](https://github.com/JetBrains/kotlin))
+  - Copyright 2010-2020 JetBrains s.r.o and respective authors and developers
 - toml4j 0.7.2: MIT ([Source](https://github.com/mwanji/toml4j))
+  - Copyright (c) 2013-2015 Moandji Ezana
+- kotlin-result 1.1.14: ISC ([Source](https://github.com/michaelbull/kotlin-result))
+  - Copyright (c) 2017-2022 Michael Bull (https://www.michael-bull.com)
 
 ## Associated notices
 
@@ -22,10 +30,6 @@ The Apache Software Foundation (http://www.apache.org/).
 ## Full license texts
 
 ### MIT
-MIT License
-
-Copyright (c)
-
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
@@ -248,3 +252,15 @@ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 
+### ISC
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.